1994 Volume 1994 Issue 40 Pages 39-42
A field study was conducted in crop fields with wheat-rice rotation in Kagawa in order to examine the relationship between the incidence of trichothecene-producing Gibberella zeae and Fusarium graminearum in the field and the occurrence of trichothecenes such as nivalenol (NIV) and deoxynivalenol (DON) in wheat. Ninety % (28/31) of G, zeae isolates from perithecia on debris of rice stubbles in wheat fields in Kagawa were mycotoxigenic, and, of these toxic isolates, 27 (96.4%) and 1 (3.6%) were NIV- and DON-producers, respectively. All of 54 isolates of dispersal G. zeae ascospores collected in a field in Miki, Kagawa, showed the toxin producibility: 46 (85.2%) and 8 (14.8%) isolates for NIV- and DON-producers, respectively. Furthermore, all of 20 isolates of F. graminearum from wheat grains harvested in the Miki-field were also toxigenic: 13 (65%) and 7 (35%) isolates for NIV- and DON-producers, respectively. The ratio of mean levels of NIV to DON in two wheat samples was 59.7% to 40.3%. Thus, the occurrence of the toxins in wheat was positively correlated to the incidence of the toxigenic fungi in the field.
